1. Field of the Invention
The present invention relates to a pivot hinge, and more particularly to a pivot hinge with two stems and a sleeve. Each stem has an extension to be received in the sleeve so that the friction required by pivotal movement is evenly distributed to two extensions and thus the life span of the pivot span is prolonged.
2. Description of Related Art
With reference to FIG. 6, a conventional pivot hinge is composed of a male part (50) and a female part (60). The male part (50) has a first stem (51) and an extension (52) integrally formed with the first stem (51). The female part (60) has a hollow cylindrical portion (61) formed to correspond to the extension (52) and a second stem (62) integrally formed with the hollow cylindrical portion (61).
When the pivot hinge of this kind is to be assembled, the extension (52) is interference fitted in the hollow cylindrical portion (61). Thereafter, with the first stem (51) and the second stem (62), the pivot hinge is adapted to securely connect to surfaces of two elements of a device respectively, such as the screen and the main frame of a laptop. When the conventional pivot hinge is in operation, the force required to maintain the screen at any desired angle is from the friction between the extension (52) and an. interior face of the hollow cylindrical portion (61). Because all the pivotal movement involves friction, after a period of time using the pivot hinge, either the extension (52) or the interior face of the cylindrical portion (61) is worn and the pivot hinge can no longer provide the required force to maintain the tilt of the screen.
To overcome the shortcomings, the present invention tends to provide an improved pivot hinge to mitigate and obviate the aforementioned problems.
The primary objective of the present invention is to provide an improved pivot hinge having two stems each provided with an extension and a sleeve provided to receive therein the two extensions so as to evenly distribute the friction to two extensions and prolong the life span of the hinge.
In order to accomplish the foregoing objective, the pivot hinge has a first stem, a second stem and a sleeve. The first stem has a body with first through holes adapted to be engaged with a surface, such as a laptop screen surface, and an extension with first grooves formed on a periphery of the extension.
The second stem has a body with second through holes adapted to be engaged with a surface, such as a laptop main frame surface, and an extension with second grooves formed on a periphery of the extension.
The sleeve is hollow and has a cutout longitudinally defined in an outer periphery of the sleeve and a pair of gaps radially defined in the periphery of the sleeve to communicate with the cutout. The sleeve further has inner grooves defined in an inner surface of the sleeve to correspond to the grooves of the first and second stems respectively.
Other objects, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.